Pulper



Dec. 24, 1968 J B ET AL PULPER 3 Sheets-Sheet 1 Filed July 11. 1966 FIG-l M 2 n 5 W2 3 4 2 3 3 I 0 II 5 5 7 2 w w 2/ 2 2 FIG-2 INVENTORS w n Km 9 mm ARM m wmw M ATTORNEYS PULPER 5 Sheets-Sheet 2 Filed July 11. 1966 FIG-4 OOGOOOQOOOOQ Dec. 24, 1968 J. A. BUCK ET AL 3,417,933

PULPER 7 Filed July 11, 1966 3 Sheets-Sheet 5 FIG-6 so FIG-l l 62 63 45 ilVAlzmlzlfllmlgm United States Patent 3,417,933 PULPER John A. Buck, Owen Sound, Ontario, and Frank D.

Taylor, North Vancouver, British Columbia, Canada, assignors to The Black 'Clawson Company, Hamilton, Ohio, a corporation of Ohio Filed July 11, 1966, Ser. No. 564,245 Claims priority, application Canada, July 12, 1965, 935,550 11 Claims. (Cl. 241--280) This machine pertains to pulpers and more particularly to machines for pulping paper, waste paper, broke, and the like for returning the same into the form of a liquid slurry stock so that it can be reused for paper making.

The invention has special relation to pulping apparatus of the type in which the stock to be pulped is directed into or contained in a tub which is provided with rotor or impeller apparatus for cutting and shearing the slurry and for causing the circulatory movement of the stock in such a manner as to create additional shearing forces and thereby effect the desired pulping and defibering action. The pulping apparatus of this general type is employed in both batch and continuous operations, and the invention is equally applicable to both types of operation.

An important object of this invention is the provision of pulping apparatus in which the stock is subjected to an axial flow and in which two or more separate stock pulping or impeller units are mounted on a common shaft for operating upon the liquid slurry stock.

A further object of this invention is the provision of a pulper in which a horizontally mounted tube or shaft in the mixing chest portion of a tub carries a propeller at one end thereof and a rotor at the other end which cooperate with a stock extraction plate for the removal of stock from the tub.

A further important object of this invention is the provision of a pulper which may be used to pulp a wide variety of paper waste products and broke, such as newsprint, book material, data cards, food container board, and the like.

A still further object of this invention is the provision of a pulping apparatus of the low profile, horizontal flow type in which there is mounted an impeller for directing the flow of the stock longitudinally across the bottom of the vat, breakers or beaters spaced from the impeller to receive stock directed from the impeller, and a further impeller mounted on a side of the tub generally opposite from the impeller and having a plurality of vanes or heaters cooperating with an extraction plate for further reduction and defibering of the pulp, and providing generally circulatory movement of the stock in the tub.

A still further object of the invention is the provision of an axial flow pulper which is designed particularly to receive the full output of a paper machine, such as a newsprint, kraft or board machine, over extended periods of time to return the broke into a slurry stock so that it can be promptly and efliciently reused and remade into salable paper.

A still further object of the invention is the provision of a pulping unit which is side driven and has lowv vertical height with an under-rotor extraction and a propeller which is mounted on the opposite side of a horizontal shaft for force-feeding the stock to the pulping rotor. Preferably, the blades of the propeller are adjustable so that the rate of movement or flow of the stock toward the pulping rotor may be controlled.

These and other objects and advantages of the present invention will become apparent from the following description, the accompanying drawings and the appended claims.

Patented Dec. 24, 1968 In the drawings FIG. 1 is a vertical section through a pulper constructed according to this invention;

FIG. 2 is a plan view, with parts partially broken away, of the pulper ches looking along the line 22 of FIG. 1;

FIG. 3 is a further vertical section taken generally along the line 3-3 of BIG. 1;

FIG. 4 is an end elevation of a dual-rotor pulper constructed according to the invention;

FIG. 5 is a plan view of the dual-rotor pulper of FIG. 4, with parts being broken away;

FIG. 6 is an enlarged partially broken away longitudinal section through one of the pulping rotors taken generally along the line 66 of FIG. 3;

FIG. 7 is a section through the shaft showing the propeller in end elevation, taken generally along the line 77 of FIG. 6;

FIG. 8 is a section through the rotor shaft showing the breaker plate in end elevation, taken generally along the line 88 of FIG. 6;

FIG. 9 is a further rotor section showing a modified breaker plate construction;

FIG. 10 is a further section through the rotor shaft showing the pulping rotor and extracting plate in end elevation, taken generally along the line 1010 of FIG. 6; and

FIG. 11 is a section through one of the pulping rotor vanes and a portion of the extraction plate taken generally along the line 1111 of FIG. 10.

Referring to the figures of the drawings which illus trate preferred embodiments of the invention, FIGS. 1-3 show pulping apparatus constructed according to this invention as including a generally four-sided vat or hopper 10 into which the material to be pulped may be placed. The hopper 10 may be placed so as to receive broke from a paper machine, and for this purpose, it is highly advantageous to form the tub with sloping side walls v11 and 12, and end walls 13 and 14. A plurality of showers or downwardly directed nozzles 15 direct the broke into the tub. Recirculating pipes 16 and overflow pipes 17 may be provided in the walls of the hopper 10 for purposes well known in the art.

The bottom portion 20 of the pulper 10 is straightsided and forms a pulping vat or tub 20 within which the pulping actually takes place. The bottom of the tub 20 may be suitably received on flooring, such as on the concrete flooring 22, shown in FIGS. 1 and 3. Alternately, the bottom may be formed of sheet metal, wood, tile, or iron as desired.

One of the important advantages of this invention is the provision of a horizontal flow pulper which comprises a shaft extending longitudinally through the tub 20 adjacent the bottom thereof. The shaft 25 is mounted for rotation on the opposite end walls 26 and '27 of the tub 20 on external bearing supports and bearings 28 and 29.

The shaft 25 includes means defining a plurality of separate stock pulping devices which are mounted axially in spaced apart relation thereon. These devices include an impeller or propeller 30 which is mounted adjacent one end of the shaft 25, one or more disintegrator or breaker plates 32 which are mounted approximately in the middle of the shaft and axially spaced from the propeller 30, and a vane-d pulping rotor 35 which is mounted adjacent the other end of the shaft within the tub 20.

Reference may be had to FIGS. 6-10 for a more detailed description of the vat 20 and the shaft impeller arrangement therein. The right hand portion of the vat 20 is double-walled with the outer vat wall 27 and a spaced inner wall 38 to form a pulp extraction box 40.

3 The box 40 has a pulp outlet 42 at the bottom thereof. A wash-out opening 43 enters the extraction box 40 near the top.

The extraction box includes means defining an annular extraction plate 45, which is shown in section in FIG. 6, and in plan view in FIG. 10. The extraction plate 45 is formed in surrounding relation to the shaft 25 and is provided with a plurality of stock outlet holes or openings 48 through which the stock may move from the interior of the vat into the extraction box 40 and to the outlet 42.

As described above, the propeller 30 is mounted adjacent one end of the shaft 25 and, as shown in FIG. 7, may be formed with four adjustable blades 50, which are held to a propeller hub 51 in predetermined adjusted position by bolts 52. A propeller blade baffle 54 may be mounted on the inside of the chest 20 over the outer periphery of the blades 50 for preventing tangential throwing of the stock upwardly into the vat so that it is directed axially toward the extraction plate 45.

The propeller also directs the stock in the vat axially into the path of the disintegrator 32. As shown in FIG. 8, the disintegrator or breaker plate 32 consists of two radially disposed blade-like projections 55 and 56 which are flanged at '57 and clamped over the shaft 25. The disintegrator causes a further reduction or breaking up of the pulp, and may 'be provided with small rectangular bars or teeth 58 welded in the periphery thereof which act as radially disposed knife-like edges or cutters for shearing and cutting larger pieces of stock and reducing the same in size. Also, the blades 55 may be formed with a slight pitch in the direction of stock movement.

The vaned rotor 35 is mounted on the shaft 25 in pulping and pumping relation to the extraction plate 45. The rotor 35 may be cast and machined with a plurality of radially extending vanes 60 which have inclined forward faces or surfaces 62 (FIG. 11) in relation to the plane of the extraction plate 45 and which have slightly upwardly trailing surfaces 63. The leading surfaces 62 of the vanes are essentially flat in vertical section and are arranged at an incline toward the working surface of the extraction plate 45 so that the surface 62 will produce a pumping action which surges the stock and will also force the stock downwardly through the openings in the plate. The trailing end portion 63 exerts a lifting action on the stock away from the surface of the extraction plate in response to the rotation of the vane. The vaned rotor 35 may be constructed according to the teachings of the patent of Vokes No. 3,073,535, issued Jan. 15, 196-3.

A rotor deflector plate 65 is mounted on the wall 27 of the vat or hopper as a deflector for the rotor 35 to redirect the material into the pulping area or chest which is not removed by the extraction bed plate 45. Any suitable means may be used for driving the rotor 25, and as shown in FIGS. 1 and 2, the shaft may be provided with a pulley 70 which is connected through suitable belting 71 to a drive motor 75.

As shown in FIG. 3, the shaft 25 is driven in the clockwise direction and the propeller directs the stock generally axially of the shaft 25 toward the opposite end of the chest 20. The axially directed stock is engaged by the breaker plate 32 which operates to reduce the particle size of the broke or other solid material in the stock, the stock is further directed axially toward the pulping rotor and the extraction plate 45. The result is that the stock is supplied under force to the pulping rotor 35. A substantial portion thereof is constantly being reduced in sufficient size to pass through the openings 48 of the extraction plate 45 and into the interior of the extraction box 40. The remainder is recirculated back to the propeller 30, and the proper consistency of the stock is maintained by the dilution and the wash-down nozzles, as new dry material to be pulped is fed into the vat.

A modified disintegrator paddle construction 32' is shown in FIG. 9 as being provided with a plurality of tangential saw-tooth shaped teeth 58, which operate substantially in the same manner as the cutter bars 58 of the breaker plate 32 of FIG. 8.

In FIGS. 4 and 5 there is illustrated a dual-rotor pulper in which a pair of rotor shafts 'are mounted in a vat in side-by-side relationship, for handling substantially increased capacity within a given space. Accordingly, the vat 110 of FIGS. 4 and 5 is shown as having a pair of the counter-rotating shafts 125, each of which shafts include the propellers 130, disintegrator plates 132 and the pulping rotor 135. Each of the shafts and the elements mounted thereon may be constructed according to the details of the embodiment described above, and as shown in FIGS. 6-10, except that the propeller and vane elements are preferably oppositely pitched to provide balanced operation, and a more uniform flow pattern.

It will therefore be seen that this invention provides pulping apparatus which is particularly adapted for mounting under paper machines to receive broke therefrom and to repulp the same in a continuous operation. The apparatus of this invention is characterized by a low profile. The arrangement of the propeller and disintegrator paddles on the common shaft, with the propeller blades preferably being adjustable in pitch, provides a controlled force feed into the pulping rotor, which has proved to be highly desirable and efiicient in operation to handle a high quantity of broke of all kinds of paper, at a continuous rate. Also, it is within the scope of this invention to use more than two rotors, where desired.

While the forms of apparatus herein described constitute preferred embodiments of the invention, it is to be understood that this invention is not limited to these precise forms of apparaus and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. A pulper comprising a tank forming a pulping vat, a shaft extending transversely of said vat adjacent the bottom thereof, an extraction plate on one end wall of said vat forming a tank outlet in surrounding relation to said shaft, a pulping rotor mounted on said shaft and having a plurality of vanes operably associated with said extraction plate for directing stock slurry therethrough, and a propeller mounted on said shaft in axially spaced relation to said rotor for directing stock under force axially toward said rotor vanes and said extraction plate.

2. A pulper of claim 1 further including means on said vat forming an extraction box to receive slurry through said extraction plate.

3. The pulper of claim 1 further including breaker plate means mounted on said shaft between said propeller and said pulping rotor in the flow of stock therebetween, said breaker plate means forming a plurality of radially disposed knife-like edges for cutting and reducing the particle size of fibrous material in said stock as the same passes from said propeller to said rotor.

4. The pulper of claim 1 in which there are a pair of said shafts each having a pulping rotor and a propeller, as defined, and each operatively associated with a separate said extraction plate, with said shafts being adapted for counter-rotation one to the other.

5. The pulper of claim 1 further comprising a breaker on said shaft including at least two radially directed por- 7. A low profile, horizontal-flow pulper comprising a tank forming a pulping chest, a shaft extending transversely of said chest adjacent the bottom thereof, an extraction plate on one end wall of said chest forming a shaft outlet in surrounding relation to said shaft, a pulping rotor mounted on said shaft and having a plurality of vanes operably associated with said extraction plate for directing stock slurry therethrough, a breaker plate mounted on said shaft spaced from said pulping rotor in the flow of stock thereto, said breaker plate having a plurality of radially disposed knife-like edges for cutting and reducing the particle size of fibrous material in said stock as the same passes from said propeller to said rotor, and a propeller mounted on said shaft in axially spaced relation to said rotor and breaker plate for directing stock under force axially toward said rotor vanes and said extraction plate.

8. The pulper of claim 7 wherein said breaker plate knife-like edges are formed by rectangular short sections of bar stock on the breaker plate periphery.

9. The pulper of claim 7 wherein said breaker plate edges are formed as saw-tooth cuts formed in the plate periphery.

10. The pulper of claim 7 in which there is a plurality of said shafts each having a pulping rotor, a breaker plate and a propeller, as defined, and each operatively associated with a separate said extraction plate, with said shafts being adapted for counter-rotation one to the other.

11. The pulper of claim 1 comprising a plurality of blades on said propeller, and means mounting said blades for adjustment of pitch angle to regulate the rate of axial flow therefrom.

References Cited UNITED STATES PATENTS 216,958 7/1879 Hudson. 1,188,493 6/1916 Ryther 241-163 XR 1,404,981 1/ 1922 LetZ 241-163 3,343,800 9/ 1967 Rasmussen 24l--280 XR HARRISON L. HINSON, Primary Examiner. 

1. A PULPER COMPRISING A TANK FORMING A PULPING VAT, A SHAFT EXTENDING TRANSVERSELY OF SAID VAT ADJACENT THE BOTTOM THEREOF, AN EXTRACTION PLATE ON ONE END WALL OF SAID VAT FORMING A TANK OUTLET IN SURROUNDING RELATION TO SAID SHAFT, A PULPING ROTOR MOUNTED ON SAID SHAFT AND HAVING A PLURALITY OF VANES OPERABLY ASSOCIATED WITH SAID EXTRACTION PLATE FOR DIRECTING STOCK SLURRY THERETHROUGH, AND A PROPELLER MOUNTED ON SAID SHAFT IN AXIALLY SPACED RELATION TO SAID ROTOR FOR DIRECTING STOCK UNDER FORCE AXIALLY TOWARD SAID ROTOR VANES AND SAID EXTRACTION PLATE. 